This study will test the effectiveness of two different tuberculosis (TB) prevention strategies, DOTS or DOTS-A. DOTS is the current prevention strategy for TB. DOTS-A is an enhanced prevention strategy that will screen household members of individuals diagnosed with active TB and will provide enhanced treatment as needed. The study will be conducted in 8 communities located in Rio de Janeiro. Study participants will include 6400 males and females of all ages, including active TB patients and their household contacts. Patients with TB identified for treatment at the Health Clinics of 8 urban communities will be eligible. The communities will be assigned to 1 of the 2 prevention strategies, DOTS or DOTS-A. After 4 years, the information gathered during the study will be used to determine the incidence of TB in these communities to see which prevention strategy was more effective in decreasing TB.